🚀 go-pugleaf

gdb 4.6 on SGI IRIX 4.0.1 does not demangle cfront generated local
variables and structure data members correctly.  Here is an example:

junk.c:
struct A {
    int i;
};

main()
{
    A a;
    a.i = 10;
}

46 lotus:~$ gdb junk
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GDB 4.6, Copyright 1992 Free Software Foundation, Inc...
No symbol "demangle" in current context.
(gdb) b 8
Breakpoint 1 at 0x400210: file junk.c, line 8.
(gdb) run
Starting program: /u/prof/mecklen/junk

Breakpoint 1, main () at junk.c:8
8           a.i = 10;
(gdb) i lo
a::a() = {
  i__1A = 0
}
(gdb) p a
No symbol "a" in current context.
(gdb) p __1a
$1 = {
  i__1A = 0
}
(gdb) p __1a.i
There is no member named i.
(gdb) p __1a.i__1A
$2 = 0
(gdb)

The code generated by cfront for this program is:

/* <<AT&T C++ Translator 2.00 06/30/89>> */
/* < junk.c > */

# 1 "junk.c"
void *__vec_new (void *, int , int , void *);

# 1
void __vec_ct (void *, int , int , void *);

# 1
void __vec_dt (void *, int , int , void *);

# 1
void __vec_delete (void *, int , int , void *, int , int );
typedef int (*__vptp)();
struct __mptr {short d; short i; __vptp f; };

# 1
struct A;struct A {     /* sizeof A == 4 */

# 2
int i__1A ;
};

# 5
int main (void ){ _main();
# 6
{
# 7
struct A __1a ;
__1a . i__1A = 10 ;
}
}
# 9

/* the end */

A bogus fix that I tried is:

diff -r gdb-4.6/gdb/cplus-dem.c gdb-4.6.mashed/gdb/cplus-dem.c
341c344,348
<       if (success && (*mangled != '\0'))
---
>       if (success == 2)
>         {
> 	  string_append( &decl, mangled );
>         }
>       else if (success == 1 && (*mangled != '\0'))
886c893
< 	Returns 1 on success, 0 otherwise.
---
> 	Returns 2 if a cfront local symbol, 1 on other success, 0 otherwise.
918c925,926
<   else if ((scan == *mangled) && (isdigit (scan[2]) || (scan[2] == 'Q')))
---
>   else if (current_demangling_style == gnu_demangling &&
> 	   (scan == *mangled) && (isdigit (scan[2]) || (scan[2] == 'Q')))
923a932,938
>   else if (current_demangling_style == cfront_demangling &&
> 	   (scan == *mangled) && isdigit (scan[2]))
>     {
>       /* A cfront local variable starts with "__<digit>". */
>       *mangled = scan + 3;
>       success = 2;
>     }

Any fixes would be much appreciated.

				Thanks,
				Robert Mecklenburg
				University of Utah